Electrostatic spray nozzle assemblies are utilized for applying oil and other coating and lubricating fluids in various manufacturing processes. Electrostatic spray nozzle assemblies, such as shown in U.S. Pat. No. 4,749,125, discharge a plurality of fluid flow streams which are electrostatically charged and atomized by means of a high voltage electrode with the assistance of a grounded induction bar for disposition onto items to be sprayed or coated, typically as they are conveyed past the spraying apparatus.
Heretofore, such electrostatic assembly spray nozzle assemblies have suffered from various operating and maintenance problems. For example, imprecise manufacture and assembly of such spray nozzles and charging electrodes can result in high voltage leakage that can significantly affect the operating efficiency of the spray operation. Fluid leakage problems also can adversely affect the spray distribution and lead to waste of costly spray liquids. While it often is desirable to direct a plurality of electro-statically charged flow streams, heretofore it has been difficult to effectively and efficiently control the liquid discharge for cyclic operation and without undesirable dripping and waste of the coating fluid.